1 files changed, 228 insertions, 0 deletions
diff --git a/src/xsub.cpp b/src/xsub.cpp
new file mode 100644
index 0000000..c4381a2
--- /dev/null
+++ b/src/xsub.cpp
@@ -0,0 +1,228 @@
+/*
+    Copyright (c) 2007-2013 Contributors as noted in the AUTHORS file
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <string.h>
+
+#include "xsub.hpp"
+#include "err.hpp"
+
+zmq::xsub_t::xsub_t (class ctx_t *parent_, uint32_t tid_, int sid_) :
+    socket_base_t (parent_, tid_, sid_),
+    has_message (false),
+    more (false)
+{
+    options.type = ZMQ_XSUB;
+
+    //  When socket is being closed down we don't want to wait till pending
+    //  subscription commands are sent to the wire.
+    options.linger = 0;
+
+    int rc = message.init ();
+    errno_assert (rc == 0);
+}
+
+zmq::xsub_t::~xsub_t ()
+{
+    int rc = message.close ();
+    errno_assert (rc == 0);
+}
+
+void zmq::xsub_t::xattach_pipe (pipe_t *pipe_, bool subscribe_to_all_)
+{
+    // subscribe_to_all_ is unused
+    (void) subscribe_to_all_;
+
+    zmq_assert (pipe_);
+    fq.attach (pipe_);
+    dist.attach (pipe_);
+
+    //  Send all the cached subscriptions to the new upstream peer.
+    subscriptions.apply (send_subscription, pipe_);
+    pipe_->flush ();
+}
+
+void zmq::xsub_t::xread_activated (pipe_t *pipe_)
+{
+    fq.activated (pipe_);
+}
+
+void zmq::xsub_t::xwrite_activated (pipe_t *pipe_)
+{
+    dist.activated (pipe_);
+}
+
+void zmq::xsub_t::xpipe_terminated (pipe_t *pipe_)
+{
+    fq.pipe_terminated (pipe_);
+    dist.pipe_terminated (pipe_);
+}
+
+void zmq::xsub_t::xhiccuped (pipe_t *pipe_)
+{
+    //  Send all the cached subscriptions to the hiccuped pipe.
+    subscriptions.apply (send_subscription, pipe_);
+    pipe_->flush ();
+}
+
+int zmq::xsub_t::xsend (msg_t *msg_)
+{
+    size_t size = msg_->size ();
+    unsigned char *data = (unsigned char *) msg_->data ();
+
+    if (size > 0 && *data == 1) {
+        //  Process subscribe message
+        //  This used to filter out duplicate subscriptions,
+        //  however this is alread done on the XPUB side and
+        //  doing it here as well breaks ZMQ_XPUB_VERBOSE
+        //  when there are forwarding devices involved.
+        subscriptions.add (data + 1, size - 1);
+        return dist.send_to_all (msg_);
+    }
+    else 
+    if (size > 0 && *data == 0) {
+        //  Process unsubscribe message
+        if (subscriptions.rm (data + 1, size - 1))
+            return dist.send_to_all (msg_);
+    }
+    else 
+        //  User message sent upstream to XPUB socket
+        return dist.send_to_all (msg_);
+
+    int rc = msg_->close ();
+    errno_assert (rc == 0);
+    rc = msg_->init ();
+    errno_assert (rc == 0);
+
+    return 0;
+}
+
+bool zmq::xsub_t::xhas_out ()
+{
+    //  Subscription can be added/removed anytime.
+    return true;
+}
+
+int zmq::xsub_t::xrecv (msg_t *msg_)
+{
+    //  If there's already a message prepared by a previous call to zmq_poll,
+    //  return it straight ahead.
+    if (has_message) {
+        int rc = msg_->move (message);
+        errno_assert (rc == 0);
+        has_message = false;
+        more = msg_->flags () & msg_t::more ? true : false;
+        return 0;
+    }
+
+    //  TODO: This can result in infinite loop in the case of continuous
+    //  stream of non-matching messages which breaks the non-blocking recv
+    //  semantics.
+    while (true) {
+
+        //  Get a message using fair queueing algorithm.
+        int rc = fq.recv (msg_);
+
+        //  If there's no message available, return immediately.
+        //  The same when error occurs.
+        if (rc != 0)
+            return -1;
+
+        //  Check whether the message matches at least one subscription.
+        //  Non-initial parts of the message are passed 
+        if (more || !options.filter || match (msg_)) {
+            more = msg_->flags () & msg_t::more ? true : false;
+            return 0;
+        }
+
+        //  Message doesn't match. Pop any remaining parts of the message
+        //  from the pipe.
+        while (msg_->flags () & msg_t::more) {
+            rc = fq.recv (msg_);
+            errno_assert (rc == 0);
+        }
+    }
+}
+
+bool zmq::xsub_t::xhas_in ()
+{
+    //  There are subsequent parts of the partly-read message available.
+    if (more)
+        return true;
+
+    //  If there's already a message prepared by a previous call to zmq_poll,
+    //  return straight ahead.
+    if (has_message)
+        return true;
+
+    //  TODO: This can result in infinite loop in the case of continuous
+    //  stream of non-matching messages.
+    while (true) {
+
+        //  Get a message using fair queueing algorithm.
+        int rc = fq.recv (&message);
+
+        //  If there's no message available, return immediately.
+        //  The same when error occurs.
+        if (rc != 0) {
+            errno_assert (errno == EAGAIN);
+            return false;
+        }
+
+        //  Check whether the message matches at least one subscription.
+        if (!options.filter || match (&message)) {
+            has_message = true;
+            return true;
+        }
+
+        //  Message doesn't match. Pop any remaining parts of the message
+        //  from the pipe.
+        while (message.flags () & msg_t::more) {
+            rc = fq.recv (&message);
+            errno_assert (rc == 0);
+        }
+    }
+}
+
+bool zmq::xsub_t::match (msg_t *msg_)
+{
+    return subscriptions.check ((unsigned char*) msg_->data (), msg_->size ());
+}
+
+void zmq::xsub_t::send_subscription (unsigned char *data_, size_t size_,
+    void *arg_)
+{
+    pipe_t *pipe = (pipe_t*) arg_;
+
+    //  Create the subsctription message.
+    msg_t msg;
+    int rc = msg.init_size (size_ + 1);
+    errno_assert (rc == 0);
+    unsigned char *data = (unsigned char*) msg.data ();
+    data [0] = 1;
+    memcpy (data + 1, data_, size_);
+
+    //  Send it to the pipe.
+    bool sent = pipe->write (&msg);
+    //  If we reached the SNDHWM, and thus cannot send the subscription, drop
+    //  the subscription message instead. This matches the behaviour of
+    //  zmq_setsockopt(ZMQ_SUBSCRIBE, ...), which also drops subscriptions
+    //  when the SNDHWM is reached.
+    if (!sent)
+        msg.close ();
+}